The present disclosure relates to a timing controller, an error detection method for the timing controller, and a display device having the timing controller, and more particularly, to a timing controller for detecting an error in an initialization operation and update operation.
A liquid crystal display (LCD) includes an LCD panel a gate driver, a data driver, and a timing controller. The LCD panel includes a thin film transistor (TFT) substrate where pixel electrodes are formed, a color filter substrate where common electrodes are formed, and a liquid crystal layer interposed between the TFT substrate and the color filter substrate. The gate driver and the data driver are configured to apply signals for display operations of the LCD panel. The timing controller is configured to generate pixel data and control signals for operations of the gate driver and the data driver.
The timing controller generally performs an initialization operation, a display operation, and an update operation in this order. The initialization operation is performed to read initialization data from an internal or external memory and set the data to allow the timing controller to operate normally. Examples of the initialization data include a resolution, a timing, a color correction, and a response time compensation. The display operation is performed to convert external input data into data necessary for image display of the LCD panel and to generate signals necessary for the gate driver and the data driver. The display operation is performed after the initialization operation is normally performed. In addition, the update operation is performed when a setting is changed during the display operation. The update operation is performed simultaneously with the display operation, and updated contents are applied to the image display in a blank period between frames.
When the initialization operation is performed normally, the timing controller generates control signals for generation of driving voltages. The driving voltages generated according to the control signals are applied to the gate driver and the data driver. In addition, the timing controller generates control signals for operations of the gate driver and the data driver. In this way, the display operation is started. When the setting is changed during the display operation, the update operation is performed simultaneously with the display operation and the updated contents are applied to the image display in a blank period between frames.
The initialization operation of the timing controller is divided into a reset period, an oscillator clock stabilization period, a resolution and timing setting period, a color correction period, a response time compensation period, and a driving voltage setting period. During the reset period, the initial state of the timing controller is stabilized. During the oscillator clock stabilization period, an oscillating unit operates normally to stabilize a clock. After the stabilization period, the timing controller performs the initialization operation. During the resolution and timing setting period, the color correction period, the response time compensation period, and the driving voltage setting period, initialization data are read from the memory and used therein. Accordingly, the timing controller communicates with the memory, and the initialization operation is completed when the communication between the timing controller and the memory is normal. In addition, the control signals caused by the set data should be normally outputted during the driving voltage setting period.
When the communication is abnormal during any one period of the initialization operation, the control signals for generating the driving voltages are not output and the display operation is not performed. That is, it can be determined that an error occurs in the initialization operation when the control signals for generating the driving voltages are not output. However, it is impossible to determine during which period of the initialization operation the error occurs. Therefore, the respective periods of the initialization operation must be checked individually and significant time must be spent on error detection. Furthermore, since the control signals are output after the initialization operation, an error occurring during the update operation cannot be detected.